초록 ▼

A wheel 100 rotatable about a main axis 106a, including: (a) a frame 111 including multiple supports 114; (b) a first series 150 of rollers 140 radially spaced from the main axis and aligned with a first plane 160a normal to the main axis, the first series of rollers spaced to form a first discontin

A wheel 100 rotatable about a main axis 106a, including: (a) a frame 111 including multiple supports 114; (b) a first series 150 of rollers 140 radially spaced from the main axis and aligned with a first plane 160a normal to the main axis, the first series of rollers spaced to form a first discontinuous rim; and (c) a second series 152 of rollers radially spaced from the main axis and aligned with a second plane 160c normal to the main axis. The second series of rollers are spaced to form a second discontinuous rim. The first and second planes are aligned parallel to and spaced from one another. Each roller 140 is: (i) rotatable about an axis normal 117 to the main axis; (ii) mounted between a pair of the supports 115; and (iii) has a lateral central cross-sectional diameter greater than the diameter of its end portions. When viewed in side elevation, the effective ground contacting surface of each of the rollers of the first series of rollers overlaps with the effective ground contacting surface of at least one diagonally adjacent roller of the second series of rollers so that the wheel is adapted to make effective ground contact through at least two of the rollers at any one time for effective travel in directions having a component parallel to the main axis. The frame is furthermore incapable of flexing sufficiently to permit the rollers from being removed or dislodged from the frame, but capable of flexing sufficiently under high loads to redistribute load stress throughout the frame.

대표청구항 ▼

The invention claimed is: 1. A wheel rotatable about a main axis, including: (a) a frame including a plurality of supports; (b) at least two series of rollers, the first of said series of rollers aligned with a first plane normal to said main axis and spaced to form a first discontinuous rim; and (

The invention claimed is: 1. A wheel rotatable about a main axis, including: (a) a frame including a plurality of supports; (b) at least two series of rollers, the first of said series of rollers aligned with a first plane normal to said main axis and spaced to form a first discontinuous rim; and (c) the second of said series of rollers radially spaced from the main axis and aligned with a second plane normal to said main axis, said second series of rollers spaced to form a second discontinuous rim, said first and second planes aligned parallel to and spaced from one another, each roller of said first and said second series of rollers being: (i) radially spaced from said main axis; (ii) rotatable about an axis normal to said main axis; (iii) mounted between a pair of said supports; and (iv) having a lateral central cross-sectional diameter greater than the diameter of its end portions, whereby, when viewed in side elevation, the effective ground contacting surface of each said roller of said first series of rollers overlaps with the effective ground contacting surface of at least one diagonally adjacent roller of said second series of rollers so that said wheel is adapted to make effective ground contact through at least two of said rollers at any one time for effective travel in directions having a component parallel to said main axis, wherein each roller of said first series of rollers is mounted on a continuous polyaxle ring, each roller axle length of said polyaxle ring having a linear axis and integrally formed with adjacent other axle lengths and extending between and through a first series of said supports. 2. A wheel according to claim 1, wherein said frame comprises two or more separately formed subframes joinable together to form a single composite wheel frame. 3. A wheel according to claim 2, wherein a first said subframe supporting said first series of rollers is integrally formed in a molding process and comprises a central hub, said first series of said supports and a first polyaxle ring. 4. A wheel according to claim 2, wherein a first of said subframes supports said first series of rollers and a second of said subframes supports said second series of rollers. 5. A wheel according to claim 4, wherein said subframes are joined by engagement means comprising complementary parts on said first and said second subframes. 6. A wheel according to claim 2, wherein said wheel comprises at least three series of rollers including two outer series of rollers and at least one inner series of rollers, one of said subframes is an inner subframe supporting one of said inner series of rollers and aligned with at least one corresponding inner plane normal to said main axis, said inner series of rollers spaced to form an inner discontinuous rim, and wherein, when said wheel is viewed in side elevation, the effective ground contacting surface of each said roller of at least one of said outer series of rollers overlaps with the effective ground contacting surface of the diagonally adjacent rollers of said inner series of rollers. 7. A wheel according to claim 6, wherein each of said series of rollers is rotatably mounted on one continuous polyaxle ring forming part of each corresponding said subframe. 8. A wheel according to claim 7, wherein said inner subframe comprises an inner rim about said main axis and at least one of said subframes comprises a hub about said main axis. 9. A wheel according to claim 8, wherein said inner rim has a central aperture with a diameter greater than the diameter of the bore defined by said hub to permit said frame to flex under high loads. 10. A wheel according to claim 7, wherein said inner subframe is capable of sufficient flexion to permit redistribution of load from the ground contact roller of said inner series of rollers to at least one roller of one of said outer series of rollers. 11. A wheel according to claim 8, wherein said wheel is mounted on a main axle extending through said inner rim and said hub and said main axle is not in physical contact with said inner rim. 12. A wheel according to claim 8, wherein said inner subframe including said inner rim is formed from substantially less material than said subframe with said hub. 13. A wheel according to claim 6, wherein the outer roller axle plane in which the outer roller axes of one of said outer series of rollers lies is not coplanar with the corresponding subframe plane in which said outer subframe supporting said outer series of rollers predominantly lies, whereby the rollers of said outer series of rollers are mounted on supports extending outwardly from said outer subframe plane to said outer roller axle plane. 14. A wheel according to claim 1, wherein said frame comprises a central hub and wherein, in use, said wheel is mounted to a main axle extending through a central bore of said central hub whereby said wheel is capable of rotating about said main axis, said main axis of fixed position relative to an article mounted on said main axle whereby said article may be caused to travel in any direction involving: (a) rotation of said wheel about said main axis; (b) rotation of one or more of said rollers about their respective transverse axes; or (c) a combination of rotation of said wheel about said main axis and rotation of one or more of said rollers about their respective transverse axes to enable diagonal travel relative to a direction of travel normal to said main axis. 15. A wheel according to claim 7, wherein each said subframe is integrally molded as a single piece. 16. A wheel rotatable about a main axis, said wheel including: (a) one or more inner series of rollers radially spaced from said main axis and aligned with an inner roller series plane normal to said main axis, each roller of said inner series of rollers circumferentially spaced to form an inner discontinuous rim; (b) a first outer series of rollers on a first side of said inner series of rollers, said first outer series of rollers radially spaced from said main axis and aligned with a first outer roller series plane, said first outer roller series plane aligned substantially normal to said main axis and said first outer series of rollers circumferentially spaced to form a first outer discontinuous rim; and (c) a second outer series of rollers on the other side to said first side of said inner series of rollers, said second outer series of rollers radially spaced from said main axis and aligned with a second outer roller series plane, said second outer roller series plane aligned substantially normal to said main axis, said second outer series of rollers circumferentially spaced to form a second outer discontinuous rim, and said second outer roller series plane substantially parallel to said inner roller series plane and said first outer roller series plane; and wherein (i) each said roller is rotatable about a roller axis: (x) lying in the plane, in which the series of rollers to which the roller belongs, lies; (y) normal to a theoretical line extending radially from said main axis through the plane in (x); (ii) each said roller has a central diameter wider than the diameter of its end portions; (iii) when viewed in side elevation, the effective ground contacting surface of each roller of said inner series of rollers overlaps with the effective ground contacting surface of the diagonally adjacent rollers of said outer series of rollers so that said wheel is adapted to make effective ground contact through at least two of said rollers at any one time for effective travel in directions having a vector component parallel to said main axis; and (iv) each of said series of rollers is mounted on a corresponding continuous polyaxle ring, each roller axle length of said polyaxle ring being linear and integrally formed with adjacent other axle lengths and extending between and through said supports. 17. A wheel according to claim 16, wherein each said polyaxle ring defines a hexagonal or octagonal shape. 18. A wheel rotatable about a main axis, including: (a) an integrally formed frame molded as a single piece and aligned with a frame plane normal to said main axis, said frame comprising (i) a central hub; (ii) a plurality of supports extending outwardly from said central hub and aligned with said frame plane; and (iii) a continuous polyaxle ring aligned with said frame plane; and (b) a race of rollers, aligned with said frame plane and spaced to form a discontinuous rim of said wheel, each said roller: (i) equally radially spaced from said main axis (ii) rotatable about an axis normal to said main axis; (iii) mounted between a pair of said supports oh a corresponding section of said polyaxle ring; and (iv) having a lateral central cross-sectional diameter greater than the diameter of its end portions, wherein said continuous polyaxle ring defines a polygonal shape, and each roller axle length of said polyaxle ring having a linear axis and integrally formed with adjacent other axle lengths and extends between and through said plurality of supports. 19. The wheel of claim 18, wherein each said support of said plurality of supports includes a radial arm extending from said central hub. 20. The wheel of claim 19, wherein said frame includes a substantially solid central disk coaxial with said main axle and formed between said central hub and said radial arms. 21. The wheel of claim 20, wherein said radial arms are in length less than half the radius of said wheel and greater than the diameter of each of said rollers.